Fluid Mixing And Dispensing Apparatus

Abstract

Two or more fluids, such as the bonding and setting adhesive agents, are mixed and dispensed by an assembly comprising a rotatable shaft that has an axial mixing chamber, radial ports extending into the chamber, and a longitudinal fluid mixture dispensing port extending forwardly from the chamber. The forward end section of the shaft is encased by a nonrotatable housing provided with fluid inlet ports adapted to be swept by the inlet ports of the shaft to meter fluid into the mixing chamber. The entire assembly is adapted for mounting to a hand-held rotary electric power tool.

Description

The present invention relates to fluid dispensing apparatus of the type intended to mix a plurality of fluids, such as multicomponent epoxy resin adhesives and the like, in desired proportions and dispense the mixed fluids either intermittently or continuously as desired. More particularly, this invention relates to such apparatus having a portable manipulatable mixing and dispensing assembly.

Multicomponent adhesives and like bonding agents have been extruded or dispensed from portable bonding guns of the type that receive a replacable reservoir cartridge containing both the bonding and setting agents separated by a puncturable divider. When the gun is to used, a plunger breaks the divider and mixes the contents of the cartridge together whereupon pressure is applied to collapse the cartridge and force the mixed components out through an extrusion or dispensing head of the gun. With devices of this type, the contents of the cartridge must be completely discharged form the gun before "set up" occurs, often resulting in wastage of the excess over the amount required for a particular job.

A primary object of the present invention is to provide dispensing apparatus having separate reservoirs for fluid components to be mixed and a component mixing assembly adapted to receive the fluid components from segregated passages and mix and dispense the components downstream of the segregated passages such that only the desired amount of admixed components need be dispensed. Another object is to provide such apparatus having a portable and manipulatable mixing and dispensing assembly. A further object is to provide such an assembly in a form that can be conveniently cleaned of residual admixed components.

These and other objects and advantages of the present invention will become apparent from the following description, in connection with the accompanying drawings, of which:

FIG. 1 is an assembly view of a preferred mixing and dispensing assembly in accordance with this invention;

FIG. 2 is a longitudinal cross section of the preferred mixing and dispensing assembly;

FIG. 3 is a transverse cross section of the preferred mixing and dispensing assembly taken along the line 3-3 of FIG. 2;

FIG. 4 is a longitudinal cross section of an alternative mixing and dispensing assembly in accordance with this invention;

FIG. 5 is a perspective view of a portable, hand-held embodiment of the present invention of a type adapted to be attached to a hand-held power drill power unit; and

FIG. 6 is a plan view in partial section of the two fluid reservoir sections of the FIG. 5 embodiment.

The apparatus of this invention is useful for mixing and dispensing such fluids as epoxy adhesives, plastic extruding materials such as polyurethane for injection molding, foaming plastics that foam shortly after the ingredients are mixed, paints of the type that require a catalyst with adhesives and bonding agents being the primary fluids.

In brief, one aspect of the present invention comprises a fluid mixing and dispensing assembly having a fluid mixing chamber rotatable within a distributor housing provided with separate fluid inlet passages and a mixed fluid outlet passage. The wall of the mixing chamber is transversely ported such that the port or ports therethrough sweep the housing fluid inlet passages during rotation of the chamber, and is longitudinally ported such that mixed fluid within the chamber can be discharged into the housing outlet passage and dispensed therefrom. The mixing chamber is preferably adapted to be axially connected to portable rotary power means. Fluid reservoir means are provided with supply lines connected to the housing fluid inlet ports and pressurizing means are provided to force the fluids through the supply lines into the housing fluid inlet ports and into the mixing chamber. Although the accompanying FIGS. depict a two fluid mixing system, it can be readily adapted to mix more than two fluids. Also, the number of rotating ports that feed the mixing chamber can be any number over 1, two such ports being depicted in the FIGS.

Referring to FIGS. 1--3, a preferred fluid mixing and dispensing assembly 10 comprises a housing 12, comprising a hollow open ended cylindrical outer shell or jacket 14 and a hollow open ended inner cylindrical sleeve bushing valve 16, a bushing valve indexing sleeve 18, and a rotatable shaft 22 provided with an internal mixing chamber 20. These components closely interfit as shown in FIG. 2 with the bushing valve 16 and axial shaft 22 being provided with frustoconical forward-facing shoulders that bear against their respective enclosing components to ensure accurate positioning of the components in relation to one another. The housing jacket 14 is provided with two rearwardly directed tubes 24--26, each containing a fluid supply passage, 28 and 30 respectively, that extends through the jacket wall at diametrically opposite points. The jacket 14 is also provided with a cleaning port 31 extending through the jacket wall at right angles to the inlet passages 28 and 30. The rearward section of the jacket wall is longitudinally cut away to provide slot 33, the forward end of which opens into an arcuate transverse indexing pin slot 35. The jacket is adapted to be attached rearwardly to a stationary frame 29 such that the jacket and the bushing valve 16 will not revolve relative to the shaft 22.

The bushing valve 16 is provided with two diametrically opposed radially aligned fluid inlet ports 32 and 34 that extend through the wall thereof and that are indexable alignable with the passages 28 and 30 as shown in FIG. 2. When the bushing valve 16 and its indexing sleeve 18 are assembled into the jacket 14, the pin 19 on the indexing sleeve will be inserted through slot 33 into slot 35. With the pin 19 positioned to one side of the slot 35 (as shown in solid line in FIG. 3), the bushing valve will be indexed such that its ports 32 and 34 will be aligned with the passages 28 and 30. With the pin 19 positioned to the opposite side of the slot 35 (as shown in dotted line in FIG. 3) the bushing sleeve will be indexed such that one of its ports 32 will be aligned with the cleaning port 31. With the pin positioned intermediate the ends of the slot 35, the passages 28 and 30 will be sealed off by the body of bushing valve 16.

The forward end section of the shaft 22 is provided with an axial fluid passage 36 that opens forwardly into an axial fluid passage 38 of the same diameter in the forward end section of the bushing valve 16. The forward end section of the shaft 22 is also provided with two diametrically opposed radially aligned fluid inlet ports 40 and 42 that are rotatably alignable with the inlet ports 32 and 34 as shown in FIG. 2.

As the shaft 22 is rotated, its inlet ports 40 and 42 will be alternately exposed to the passages 28 and 30 through the ports 32 and 34 aligned therewith. Thus, when two fluids to be mixed are supplied under pressure through passages 28 and 30, each inlet port 40 and 42 will alternately meter a small amount of fluid from each passage into the mixing chamber 20 (that part of the passage 36 that intersects the ports 40 and 42) as the shaft 22 is rotated at a fairly rapid speed, mixing occurs substantially instantaneously between the ports 40 and 42 and the mixed fluid, still under pressure, is dispensed forwardly through passages 36 and 38 from the assembly 10.

The forward section of the shaft 22 preferably terminates within the bushing valve 16 as shown in FIG. 2 such that the mixed fluid is dispensed from the assembly 10 by a nonrotating element. This arrangement prevents the fluid mixture from splattering or spraying as might be the case if dispensed by the rotating shaft 22. Of course, if the sprayed affect is desired, the shaft could extend forwardly of the bushing valve 16.

The FIGS. 1--3 embodiment of the assembly 10 would be preferred where the jacket 14 and the shaft 22 are fabricated from metal. The intervening bushing valve 16 would be fabricated from a suitable bushing material such as Teflon or the like such that close tolerances can be maintained without creation of severe frictional resistance.

In the event that the valving function of element 16 is not required, as where cleaning port 31 is not required and where the power source will stop the shaft 22 out of registry with the ports 32--34 for example, element 16 can be provided solely for its low frictional resistance characteristics.

If one or the other of elements 14 and 22 is fabricated from a low friction material such as Teflon or the like, preferably jacket 14, the intervening bushing 16 could be eliminated. Such as embodiment is shown in FIG. 4 wherein the inner surface of jacket 14 has the confirmation of the inner surface of bushing 16 in the FIGS. 1--3 embodiment, and wherein the ports 28--30 extend radially inward as the ports 32--34 of the FIGS. 1--3 embodiment. In the FIG. 4 embodiment, the rotary power source for shaft 22 would, by cam action or otherwise, stop the shaft 22 such that its ports 40--42 were out of registry with the ports 28--30 so that there will be no fluid mixing after the power source is turned off.

FIGS. 5 and 6 depict a preferred embodiment of the invention as an attachment for a hand operated portable electric drill. In this embodiment, a frame 50 is removably attached to the motor casing of the drill 52 by any suitable means. The frame 50 includes a forwardly extending section provided to receive and hold the jacket 14 of assembly 10 axially of the drill chuck 54. The shaft 22 would be inserted and retained by the chuck 54 in the same manner as a drill bit. The frame 50 also includes a rearwardly extending section provided with two fluid reservoir members 56 and 58 which are in fluid communication with the tubes 24--26 of the assembly 10 by means of flexible fluid supply lines 60 and 62.

The reservoir members each comprise a hollow cylinder 64--66, and a spring actuated plunger 68--70 cross connected by a link 72. The link 72 slides axially along the rod 76. The rod 76 is threaded such that it can be screwed into the frame 50 to compress the spring 78 between the link 72 and the knob 80 of the rod 76. Compressing the spring 78 increases the force applied to drive the plungers 68--70 into their respective cylinders 64--66. Volumes of fluids may be supplied in disposable and collapsible plastic containers which are adapted to be inserted into the cylinders and collapsed by pressure of the spring-loaded plungers. The cylinder plungers 68--70 can be extended into their respective cylinders in unison and the cylinders 64--66 can be sized such that the fluid forced therefrom will be proportioned to the cylinder volume to provide fluid metering rather than providing for such metering at the inlets to the mixing chamber 20 of the assembly 10. The supply lines 60--62 are shown slip fitted onto the tubes 24--26 of the assembly 10 and attached to the head ends of the respective cylinders 64--66 by threaded couplings 82--84.

The FIGS. 5--6 embodiment is especially suited for the mixing and dispensing of small quantities of fluids. For larger applications, larger, remotely located reservoirs may be provided with flexible fluid supply lines provided to transport the fluids to be mixed to mixing and dispensing assembly 10. Also, for larger applications, the assembly 10 may require an articulated mounting arm suspension mechanism to provide the necessary operability and maneuverability.

Furthermore, the power source for rotating the shaft 22 could be an air motor or any other suitable device. Similarly, the means for forcing the fluids from their respective reservoirs could provide pressurized air or gas to develop the necessary force, or the like.

It is believed that the invention will have been clearly understood from the foregoing detailed description of my now preferred illustrated embodiment. Changes in the details of construction may be resorted to without departing from the spirit of the invention.

Claims

1. A fluid mixing and dispensing apparatus comprising a hollow rotatable shaft means ported to provide an internal mixing chamber, at least one fluid inlet port transversely extending through the wall of said shaft means to provide fluid communication with said mixing chamber, and fluid outlet means extending longitudinally of said shaft for egress of the mixed fluid from the mixing chamber, housing means enclosing and extending forwardly of the shaft means having transverse ports adapted to be aligned with the ports of the shaft, and sleeve means for prohibiting communication between the ports of the shaft and the ports of the housing means when the apparatus is not dispensing whereby when the apparatus is in operation fluid entering through the ports in the housing means are swept by the shaft inlet ports, mixed and dispensed through the fluid outlet means and the supply is terminated when the apparatus is not in

2. An apparatus as set forth in claim 1 wherein the sleeve means is a low friction bushing member adapted to turn through only a limited arc disposed between the shaft member and the housing means, said bushing member having transverse ports alignable with the ports of the housing

3. Apparatus according to claim 1 including indexing means permitting indexing of the bushing member transfer ports into and out of alignment

4. An apparatus according to claim 3 including a separate port for flushing the mixing chamber whereby the bushing member may be indexed out of alignment with the inlet ports and be in alignment with the flushing ports enabling the operator to halt the flow of fluid to be mixed and flush the mixing chamber without removing the material to be mixed or disassembling

5. Apparatus according to claim 1 including power means for rotating said shaft means, reservoir means for storing segregated volumes of fluids to be mixed, means providing fluid passages to said housing means inlet ports, and means for forcing stored fluids through said fluid passages.

6. Apparatus according to claim 5 including mounting means adapted to permit insertion of said shaft means into a tool chuck of a rotary power

7. Apparatus according to claim 6 wherein said reservoir means are carried by said mounting means, and wherein said means for forcing stored fluids

8. Apparatus according to claim 6 wherein said reservoir means are carried by said mounting means and comprise a cylinder for each fluid to be mixed and a plunger acting in each cylinder, a link cross connecting the plungers, and adjustable spring loading means adapted to bear against said link such that said plungers extend into their respective cylinders in unison such that the relative rates of fluid supply therefrom are proportional to the relative cross-sectional areas of said cylinders.